Issue - 299 - Bug and clarification regarding correlation sets

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Issue - 299 - Bug and clarification regarding correlation sets

Status: received
Date added: 12 Jun 2006
Date submitted: 12 June 2006
Submitter: Thomas Schulze
Description: Paragraph 3 in section 9.2 contains some invalid statements regarding the content of the <invoke>, <receive> and <reply> activities, the <onMessage> branch of <pick>, the <onEvent> variant of <eventHandlers> and the attribute "initiate". It currently says that element <correlationSet> can be used there and carries the attribute "initiate".
But it should say that for the element <correlation>.

Additionally a clarification in 9.2 would be helpful what the usage of correlation sets on a <reply> or one-way <invoke> with initiate="no" is for.
Submitter's proposal:

Section 9.2, paragraph 3, change from:

> "The <correlationSet> specifications are used in <invoke>, <receive>,
> and <reply> activities (see 10.3. Invoking Web Service Operations and
> 10.4. Providing Web Service Operations); in the <onMessage> branches of
> <pick> activities, and in the <onEvent> variant of <eventHandlers> (see
> 11.5. Pick and 12.5.1. Message Events). These <correlationSet>
> specifications identify the correlation sets by name and are used to
> indicate which correlationSet's (i.e., the corresponding property sets)
> occur in the messages being sent and received. The initiate attribute on
> a <correlationSet> specification is used to indicate whether the
> correlation set is being initiated."

to:

"The <correlationSet> specifications are used in <invoke>, <receive>, and <reply> activities (see 10.3. Invoking Web Service Operations and 10.4. Providing Web Service Operations); in the <onMessage> branches of <pick> activities, and in the <onEvent> variant of <eventHandlers> (see 11.5. Pick and 12.5.1. Message Events). The <correlation> specifications identify the correlation sets by name and are used to indicate which correlation sets (i.e., the corresponding property sets) occur in the messages being sent and received. The initiate attribute on a <correlation> specification is used to indicate whether the correlation set is being initiated."

After the following paragraph (#9 I think):

> "In the case of <invoke>, when the operation invoked is a
> request/response operation, a pattern attribute on the <correlationSet>
> specification is used to indicate whether the correlation applies to the
> outbound message (“request”), the inbound message (“response”), or both
> (“request-response”). The pattern attribute used in <invoke> is required
> for request-response operations, and disallowed when a one-way operation
> is invoked. Any violation of this rule MUST be detected during static
> analysis."

Add the following new paragraph for clarification:

> "In the case of <invoke>, when the operation invoked is an one-way
> operation, or in the case of <reply> the usage of correlation sets with
> initiate="no" is for message validation purposes only. With this, a
> business process can ensure that the response message to be send carries
> the expected correlation tokens."

Change the following paragraph for clarification, from:

> "A message can carry the tokens of one or more correlationSet’s. The
> first example shows an interaction in which a purchase order is received
> in a one-way inbound request and a confirmation including an invoice is
> sent in the one-way response. The PurchaseOrder correlationSet is used
> in both activities so that the one-way response can be correlated to the
> request at the buyer. The <receive> activity initiates the PurchaseOrder
> correlationSet. The buyer is therefore the leader and the receiving
> business process is a follower for this correlationSet. The <invoke>
> activity sending the one-way response also initiates a new
> correlationSet called Invoice. The business process is the leader of
> this correlated exchange and the buyer is a follower. The response
> message is thus a part of two separate conversations, and forms the
> bridge between them."

to:

> "A message can carry the tokens of one or more correlationSet’s. The
> first example shows an interaction in which a purchase order is received
> in a one-way inbound request and a confirmation including an invoice is
> sent in the one-way response. The PurchaseOrder correlationSet is used
> in both activities so that the one-way response is validated against the
> correlation set to correlate with the request of the buyer. The
> <receive> activity initiates the PurchaseOrder correlationSet. The buyer
> is therefore the leader and the receiving business process is a follower
> for this correlationSet. The <invoke> activity sending the one-way
> response also initiates a new correlationSet called Invoice. The
> business process is the leader of this correlated exchange and the buyer
> is a follower. The response message is thus a part of two separate
> conversations, and forms the bridge between them."

Change the last paragraph in 9.2 for clarification, from:

> "An <invoke> can consist of two messages: an outgoing request message
> and an incoming reply message. The correlationSet’s applicable to each
> message must be separately considered, because they can be different. In
> this case the PurchaseOrder correlation applies to the outgoing request
> that initiates it, while the Invoice correlation applies to the incoming
> reply and is initiated by the reply. Because the PurchaseOrder
> correlation is initiated by an outgoing message, the buyer is the leader
> of that correlation. However, the buyer is a follower of the Invoice
> correlation because the values of the correlation properties for Invoice
> are initiated by the seller in the reply received by the buyer. "

to:

> "An <invoke> can consist of two messages: an outgoing request message
> and an incoming reply message. The correlationSet’s applicable to each
> message must be separately considered, because they can be different. In
> this case the PurchaseOrder correlation applies to the outgoing request
> that initiates it, while the Invoice correlation applies to the incoming
> reply and is initiated by the reply. Because the PurchaseOrder
> correlation is initiated by an outgoing message, the buyer is the leader
> of that correlation. However, the buyer is a follower of the Invoice
> correlation because the values of the correlation properties for Invoice
> are initiated by the reply message of the seller received by the buyer."

Changes: 12 Jun 2006 - new issue

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